This disclosure generally relates to downhole sensors, and more particularly to sensors for performing in-situ analyses of formation fluid properties.
Hydrocarbons, such as oil and gas, are commonly obtained from subterranean formations that may be located onshore or offshore. The development of subterranean operations and the processes involved in removing hydrocarbons from a subterranean formation are complex. Typically, subterranean operations involve a number of different steps such as, for example, drilling a wellbore through and/or into the subterranean formation at a desired well site, treating the wellbore to optimize production of hydrocarbons, and performing the necessary steps to produce and process the hydrocarbons from the subterranean formation. Some or all of these steps may utilize a reservoir model that permits a detailed characterization of the formation (e.g., its chemical composition, heterogeneity, multi-phase zones, fluid transport trend, etc.) to guide associated operations.
Thermo-physical properties of formation fluids may be used to formulate a reservoir model. Example thermo-physical properties include, but are not limited to, specific heat capacity, thermal conductivity, molecular weight, fluid density, viscosity, and mass diffusivity. In situ (i.e. downhole) measurements of these properties may be ideal to avoid phase changes within the formation fluids that occur when they are sent to the surface for testing. Yet, many of the thermo-physical properties (e.g., heat capacity, thermal conductivity, molecular weight) are typically determined in a laboratory due to the lack of capable downhole sensors. The resulting phase changes may reduce the accuracy of the corresponding measurements. Additionally, laboratory analysis may take days and weeks, adding time and expense to the operations.
While embodiments of this disclosure have been depicted and described and are defined by reference to example embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.